CDC Says 10,000 at Risk of Hantavirus From Yosemite

The Centers for Disease Control and Prevention said Friday that 10,000 people who camped at Yosemite National Park this summer may be at risk of developing deadly hantavirus pulmonary syndrome.

Six people have been confirmed with the disease since June 10, and two died, the Atlanta-based public health agency said in an official health advisory. More suspected cases are under investigation, the CDC said.

CDC health advisories are issued to urge state public health officials and health-care providers across the country in the event of an outbreak, to be on the lookout for symptoms in potential patients.

Four of the patients who developed HPS stayed in "Signature Tent Cabins" in the Boystown area of Curry Village, the advisory said. The park's website describes the tent cabins as "a step up from your regular heated tent cabin," with insulated paneling "to help keep you cozier at night." A June 2013 stay on a weekend night costs $147 a night after tax.

The accommodations of the remaining two patients were still being researched, the CDC said.

"People who stayed in the tents between June 10 and August 24 may be at risk of developing HPS in the next six weeks," the advisory said. That amounts to an estimated 10,000 people, the agency said.

HPS, as it's known, is a severe viral disease contracted by breathing in small viral particles released into the air from the urine or droppings of infected deer mice or other infected rodents. About 36% of those who contract the disease die. There is no specific treatment, but early diagnosis and supportive care "greatly increase the chance of survival," the agency said.

The incubation period is normally two to four weeks, but can range from six days to six weeks, the CDC said. Symptoms are common to many ailments: fever, chills, cough, headaches and an upset stomach.

Guests in the tent cabins were moved on Aug. 24 and the tents were disinfected.

Approximately 2,900 people who made reservations to stay in the cabins during the period in question were sent health advisories urging them to seek immediate medical attention if they or others in their party develop symptoms, the CDC said.

A spokesman for Yosemite didn't immediately respond to a phone call requesting comment.

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